T7 RNA polymerase (T7 RNAP) is one of the simplest known RNA polymerases. Its unique structural features make it a critical model for studying the mechanisms of RNA synthesis. This review systematically examines the static crystal structure of T7 RNAP, beginning with an in-depth examination of its characteristic “thumb”, “palm”, and “finger” domains, which form the classic “right-hand-like” architecture. By detailing these structural elements, this review establishes a foundation for understanding the overall organization of T7 RNAP. This review systematically maps the functional roles of secondary structural elements and their subdomains in transcriptional catalysis, progressively elucidating the fundamental relationships between structure and function. Further, the intrinsic flexibility of T7 RNAP and its applications in research are also discussed. Additionally, the review presents the structural diagrams of the enzyme at different stages of the transcription process, and through these diagrams, it provides a detailed description of the complete transcription process of T7 RNAP. By integrating structural dynamics and kinetics analyses, the review constructs a comprehensive framework that bridges static structure to dynamic processes. Despite its advantages, T7 RNAP has a notable limitation: it generates double-stranded RNA (dsRNA) as a byproduct. The presence of dsRNA not only compromises the purity of mRNA products but also elicits nonspecific immune responses, which pose significant challenges for biotechnological and therapeutic applications. The review provides a detailed exploration of the mechanisms underlying dsRNA formation during T7 RNAP catalysis, reviews current strategies to mitigate this issue, and highlights recent progress in the field. A key focus is the semi-rational design of T7 RNAP mutants engineered to minimize dsRNA generation and enhance catalytic performance. Beyond its role in transcription, T7 RNAP exhibits rapid development and extensive application in fields, including gene editing, biosensing, and mRNA vaccines. This review systematically examines the structure-function relationships of T7 RNAP, elucidates the mechanisms of dsRNA formation, and discusses engineering strategies to optimize its performance. It further explores the engineering optimization and functional expansion of T7 RNAP. Furthermore, this review also addresses the pressing issues that currently need resolution, discusses the major challenges in the practical application of T7 RNAP, and provides an outlook on potential future research directions. In summary, this review provides a comprehensive analysis of T7 RNAP, ranging from its structural architecture to cutting-edge applications. We systematically examine: (1) the characteristic right-hand domains (thumb, palm, fingers) that define its minimalistic structure; (2) the structure-function relationships underlying transcriptional catalysis; and (3) the dynamic transitions during the complete transcription cycle. While highlighting T7 RNAP’s versatility in gene editing, biosensing, and mRNA vaccine production, we critically address its major limitation—dsRNA byproduct formation—and evaluate engineering solutions including semi-rationally designed mutants. By synthesizing current knowledge and identifying key challenges, this work aims to provide novel insights for the development and application of T7 RNAP and to foster further thought and progress in related fields.

OBJECTIVE: To investigate the effectiveness of Xuanshen Yishen Decoction (XYD) in the treatment of hypertension. METHODS: Hospital electronic medical records from 2019-2023 were utilized to emulate a randomized pragmatic clinical trial. Hypertensive participants were eligible if they were aged ⩾40 years with baseline systolic blood pressure (BP) ⩾140 mm Hg. Patients treated with XYD plus antihypertensive regimen were assigned to the treatment group, whereas those who followed only antihypertensive regimen were assigned to the control group. The primary outcome assessed was the attainment rate of intensive BP control at discharge, with the secondary outcome focusing on the 6-month all-cause readmission rate. RESULTS: The study included 3,302 patients, comprising 2,943 individuals in the control group and 359 in the treatment group. Compared with the control group, a higher proportion in the treatment group achieved the target BP for intensive BP control [8.09% vs. 17.5%; odds ratio (OR)=2.29, 95% confidence interval (CI)=1.68 to 3.13; P<0.001], particularly in individuals with high homocysteine levels (OR=3.13; 95% CI=1.72 to 5.71; P<0.001; P for interaction=0.041). Furthermore, the 6-month all-cause readmission rate in the treatment group was lower than in the control group (hazard ratio=0.58; 95% CI=0.36 to 0.91; P=0.019), and the robustness of the results was confirmed by sensitivity analyse. CONCLUSIONS XYD could be a complementary therapy for intensive BP control. Our study offers real-world evidence and guides the choice of complementary and alternative therapies. (Registration No. ChiCTR2400086589).
Adult ; Aged ; Female ; Humans ; Male ; Middle Aged ; Antihypertensive Agents/pharmacology* ; Blood Pressure/drug effects* ; Drugs, Chinese Herbal/pharmacology* ; Hypertension/physiopathology* ; Patient Readmission ; Treatment Outcome

Oligodendrocyte lineage cells, including oligodendrocyte precursor cells (OPCs) and oligodendrocytes (OLs), are essential in establishing and maintaining brain circuits. Autophagy is a conserved process that keeps the quality of organelles and proteostasis. The role of autophagy in oligodendrocyte lineage cells remains unclear. The present study shows that autophagy is required to maintain the number of OPCs/OLs and myelin integrity during brain aging. Inactivation of autophagy in oligodendrocyte lineage cells increases the number of OPCs/OLs in the developing brain while exaggerating the loss of OPCs/OLs with brain aging. Inactivation of autophagy in oligodendrocyte lineage cells impairs the turnover of myelin basic protein (MBP). It causes MBP to accumulate in the cytoplasm as multimeric aggregates and fails to be incorporated into integral myelin, which is associated with attenuated endocytic recycling. Inactivation of autophagy in oligodendrocyte lineage cells impairs myelin integrity and causes demyelination. Thus, this study shows autophagy is required to maintain myelin quality during aging by controlling the turnover of myelin components.
Animals ; Autophagy/physiology* ; Oligodendroglia/metabolism* ; Myelin Sheath/physiology* ; Aging/pathology* ; Myelin Basic Protein/metabolism* ; Cell Lineage/physiology* ; Mice ; Oligodendrocyte Precursor Cells ; Mice, Inbred C57BL ; Brain/cytology* ; Cells, Cultured ; Cell Count

Objective To conduct a scoping review of studies related to gamified physical activity interventions for pediatric cancer patients,and to extract the gamification elements and application effects within physical activity intervention programs.Methods A computer-assisted search was conducted in CNKI,Wanfang Data,VIP Database,China Biology Medicine disc,Cochrane Library,PubMed,Embase,and Web of Science for studies on gamified physical activity interventions in pediatric cancer patients,with a search period from database inception to December 31,2023.The included literature was screened,summarized,and analyzed.Results A total of 18 articles were included,including 9 randomized controlled trials,4 quasi-experimental studies,and 5 mixed-method studies.The gamified intervention programs for physical activity in children with cancer integrated 7 gamification elements,including goal setting,capacity to overcome challenges,providing feedback on performance,reinforcement,progress monitoring,social connectivity,and fun and playfulness.The types of physical activity in the intervention programs included aerobic exercise,balance training,strength training,endurance training,etc.The intensity of the activities was mainly low to moderate;the duration was mostly 30～60 minutes per session;the intervention duration ranged from 5 weeks to 1 year.Numerous research findings indicate that gamified physical activity interventions for children with cancer can help improve physical function,quality of life,and fatigue levels.However,there is signi-ficant controversy regarding their impact on improving physical activity levels.Conclusion The gamified inter-vention for physical activity in children with cancer was safe and feasible.It is recommended that in the future,personalized and phased gamified intervention programs should be developed to evaluate the intervention effects.

Postoperative infection of internal fixation of closed fractures the lower limbs in adults represents a devastating complication, characterized by diagnostic challenges, prolonged treatment duration and high disability rates. Current management of these infections faces multiple challenges, such as difficulties in early accurate diagnosis, and various controversies about the treatment plan, leading to poor overall diagnosis and treatment results. To address these issues, based on evidence-based medicine and principles with emphasis on scientific rigor, clinical applicability and innovation, the Trauma Branch of the Chinese Medical Association, Orthopedic Branch of the Chinese Medical Doctor Association, Orthopedics Branch of the Chinese Medical Association, and Trauma Orthopedics and Polytrauma Group of the Resuscitation and Emergency Committee of the Chinese Medical Doctor Association have collaboratively organized a panel of relevant experts to develop the Guideline for diagnosis and treatment of infection after internal fixation of closed lower limb fractures in adults ( version 2025). The guideline proposed 10 recommendations, aiming to provide a foundation for standardized diagnosis and treatment of postoperative infection in adults with closed lower limb fractures.

Paraplegia caused by spinal cord injury is a serious neurological complication, for which surgery is currently the main treatment method. Due to different surgical approaches, patients are usually expected to maintain a passive prone position for a long time or switch between the supine and prone positions. Affected by multiple factors such as neurogenic sensory disorders, pathological changes in muscle tone and operative duration, the risk of intraoperative acquired pressure injury (IAPI) is significantly increased. Current clinical prevention strategies for IAPI in these patients predominantly focus on localized pressure relief during positioning, lacking systematic, standardized comprehensive prevention protocols or evidence-based guidelines. To address it, Department of Nursing, Orthopedics Branch, China International Exchange and Promotive Association for Medical and Health Care, Spinal Trauma Professional Committee, Orthopedics Branch, Chinese Medical Doctor Association, Nursing Group of Spine and Spinal Cord Professional Committee of Chinese Association of Rehabilitation Medicine organized experts in relevant fields to formulate Guideline for the prevention of intraoperative acquired pressure injury in paraplegic patients with spinal cord injury ( version 2025), based on evidence-based medical evidence and latest research results and clinical practice at home and abroad. Eleven recommendations were put forward from the aspects of preoperative risk assessment, intraoperative prevention strategies, postoperative handover and monitoring, and supportive mechanisms for IAPI prevention, aiming to standardize the prevention measures and management strategies of IAPI in paraplegic patients with spinal cord injury and accelerate the recovery of patients and improve the therapeutic effect.

Aim To evaluate the continuous flow exposure sys-tem at the air-liquid interface(ALI)in vitro to provide reference data for in vitro studies on inhalation toxicology,and to conduct a preliminary evaluation of the inhalation toxicity of the com-pound limonene by using the system in conjunction with an ALI culture model of Calu-3 cells.Methods Fluorescein sodium(Na-flu)dosimetry supplemented with quartz microbalance(QCM)was used to evaluate the deposition volume and pore-to-pore homogeneity of the ALI continuous flow exposure system;limonene aerosol was exposed to an ALI-cultured model of Calu-3 cells for 3 h using the ALI continuous flow exposure system at exposure doses of high(0.213 μg·cm-2),medium(0.104μg·cm-2),low(0.064 5 μg·cm-2),clean air exposure was used as a negative control group,and the activity,lactate dehydrogenase(LDH)release,trans-epithelial electrical resist-ance(TEER),mucin MUC5AC and inflammatory factor gene expression of the exposed cells were detected after 24 h to evalu-ate the inhalation toxicity of limonene.Results The deposition of sodium fluorescein in the ALI continuous flow exposure system was 0.085±0.007 μg/30 min/well,and inter-well homogeneity was optimized from the initial 26％to less than 10％after sever-al debugging sessions;compared with the control group,there was no significant change in cellular activity and IL-8 gene ex-pression,but cellular IL-6 gene expression increased after limo-nene aerosol exposure;the mid-exposure dose of limonene pro-moted cellular release of LDH and inflammatory factor gene ex-pression.The medium exposure dose of limonene induced the cells to release LDH＞10％and decreased the expression of cel-lular tumor necrosis factor TNF-α gene;the high exposure dose of limonene decreased the cellular TEER value,impaired the cellular barrier function,and increased the expression of cellular mucin MUC5AC gene.Conclusions The ALI continuous flow exposure system can be used for inhalation toxicity in vitro stud-ies after commissioning;high and medium exposure doses of limonene are inhalation toxic.

Aim To evaluate the continuous flow exposure sys-tem at the air-liquid interface(ALI)in vitro to provide reference data for in vitro studies on inhalation toxicology,and to conduct a preliminary evaluation of the inhalation toxicity of the com-pound limonene by using the system in conjunction with an ALI culture model of Calu-3 cells.Methods Fluorescein sodium(Na-flu)dosimetry supplemented with quartz microbalance(QCM)was used to evaluate the deposition volume and pore-to-pore homogeneity of the ALI continuous flow exposure system;limonene aerosol was exposed to an ALI-cultured model of Calu-3 cells for 3 h using the ALI continuous flow exposure system at exposure doses of high(0.213 μg·cm-2),medium(0.104μg·cm-2),low(0.064 5 μg·cm-2),clean air exposure was used as a negative control group,and the activity,lactate dehydrogenase(LDH)release,trans-epithelial electrical resist-ance(TEER),mucin MUC5AC and inflammatory factor gene expression of the exposed cells were detected after 24 h to evalu-ate the inhalation toxicity of limonene.Results The deposition of sodium fluorescein in the ALI continuous flow exposure system was 0.085±0.007 μg/30 min/well,and inter-well homogeneity was optimized from the initial 26％to less than 10％after sever-al debugging sessions;compared with the control group,there was no significant change in cellular activity and IL-8 gene ex-pression,but cellular IL-6 gene expression increased after limo-nene aerosol exposure;the mid-exposure dose of limonene pro-moted cellular release of LDH and inflammatory factor gene ex-pression.The medium exposure dose of limonene induced the cells to release LDH＞10％and decreased the expression of cel-lular tumor necrosis factor TNF-α gene;the high exposure dose of limonene decreased the cellular TEER value,impaired the cellular barrier function,and increased the expression of cellular mucin MUC5AC gene.Conclusions The ALI continuous flow exposure system can be used for inhalation toxicity in vitro stud-ies after commissioning;high and medium exposure doses of limonene are inhalation toxic.